TUNING GNU GO

Here are 4 html pages devoted to tuning GNU Go. To fully understand
these pages, you may want to consult the Texinfo documentation
included with the distribution. GNU Go 3.0 (which will be similar
to the current development versions, 2.7.xx) will support two main
types of tuning:

There are many mistakes by GNU Go (white) in this game, but let's
look at the situation at move 40.
Clearly J2 is an error: the move at K2 would
connect the two groups at the bottom.

Open an rxvt window and rungnugo -l tune.sgf --quiet -L40 -T
to obtain the colored display:

This confirms that the G3 and L3 strings are
not amalgamated, since they are assigned different letters
u and v. They are considered distinct
dragons (good).

Furthermore we see that the owl code has evaluated both of them,
since they are colored in the second diagram, and that the owl
code believes G3 to be critical (red) and H3 to
be alive (green). One might argue with this assessment, but it
shows that the object of connecting them will be highly valued by
GNU Go.